Method of securing alpha tread to alpha tire carcass



May 12, 1931. w. c. STATE v 1,805,026

METHOD OF SECURING A TREAD TO A TIRE CARCASS Filed Sept.' 7, 1928 RegisteredY May 12, 1931 UNITED ASfr-MES PATENT .or-Fics- WILL c. STATE, or AKRON, o1-iro, AssIGNcR To THE GOODYEAB'TIRE se RuBBERcoM- PANY, or AKRON, OHIO, A coRPonATToN or` OHIO Application filedpSepte-mber Y Thisinvention relates to methods Vof and apparatus for constructing tire casings, anc it has particular relation to a novel method of applying a.- tread to a tire carcass and to an apparatus adapted to be employed in practicing the method.

It has been proposed to vulcanize a tread to a tire carcass by utilizing electrically energized heating devices, which-are interposed between the tread and the carcass to cause vulcanization of the elements, andthey constitute a partof the completed article.

The heating elements heretofore employed have been preformed by various "methods prior to their application to the tire carcass, and are-consequently expensive. Furthermore, theyl are very. bulky and by their presence between the tread and the carcass they cause a weak and imperfect union between these `two elements.

One object. of this invention is to obviate theabove-mentioned disadvantages by the provision of a novel methodwhich involves the application ofl a continuous length of electrical' conductor directly tothe carcass of the tire, whereby no preforming of the electrical heating element -is lnecessary and the element serves to strengthenrather than to weakeny the bond between the tread and the tire carcass in the completed aricle.

Another object ofthe invention isto provide a simple andv efficient apparatus, where- .by a continuous length of resistance wire'may `be'circumferentially applied in spaced convolutions to a tire carcass to Vserve as a heating element for vulcanizing a tread thereto.

Forv abetter understanding of the invention reference may now be4 had tothe accompanying drawings forming apart of the disclosure, wherein:

Figure 1 is a side elevational view of an apparatus embodyingcertainfeatures of the invention Figure 2 is a fragmentary plan view, on a larger scale, of a portionof the apparatus shown in FigureA 1;

Figure is afragmentary detail View, partially'in section and partially in elevation, illustrating a mechanism for moving the 7, lees. seria Noren-1,497.

wire-supplying means as ythe chuck Vis rol tated;

Figure l 1s a fragmentary detail view, on a larger scale, of a portion of the structure shown in Figure 3; and` -Y Figure 5 is a cross-sectional view illustrating the manner in which thetread and tire are confined for vthe vulcanizing operation; The method herein described involvesthe mounting of a tire carcass for rotationl about` its axis, the application of a gum strip tothe carcass circumferentially, and the application ofk an electrical conductor of comparatively high resistance arranged lin spaced convolutions about the .circumference ofthe carcass. A semi-cured tread is then applied to the carcass and is bound thereto by a fabric wrapping Strip. Anairbag disposed within the carcass is inflatedto provide the necessaryfpressure and the heating element, composed ofthe spaced 'convol11tions;of re sistance wire, is energizd to cause vulcanization of the tread to the tire carcass.r

vThe apparatus shown inthe accompanying drawings, broadly' considered, involves .asupporting stand havlng a shaft gournalled therein which carries a tire-supporting chuck. i A wire-supplying mechanism is movably secured to ank extending portion ofi the stand and means is providedA for moving the wire-supplying mechanism axially of the tire carcass, that is,in`a direction parallel to the` aXisof the carcass, as the latter is rotated.

This vmovement causes the wire to be. wound in spaced vconvolutions upon the carcass.

In theaccompanying .drawings a stand 10 rotatably supports a shaft 12 which haskeyed to one end thereof an adjustable tire chuck 13. e A motor 14 secured tothe base offthe stand 10 serves to rotate the shaft 12 through the agency of a chain 15 trained about a sprocket wheel 16 on theshaft of the motor `and a sprocket wheel 17 rigidly secured tothe shaft 12. l l

As shown, a` tire carcass 18^and an airbag 19 disposed therein are mounted inthe usual manner upon a pair of coacting `rings V21 which are secured together by bolts 22 traversing the inwardly eXtending-lianges of the rings. Rcgistratinggrooves 23are provided in the rings 21 to accommodate the valve stem 24 of the airbag. A plurality of arms 25, threaded into bosses 26 extending radially outwardly from the hub 27 of the chuck 13, are provided with hand Wheels 28 whereby they maybe adjusted into and out of engagement with the rings 21 upon which the tire carcass 18 is mounted.

An extension 29integral with orotherwise rigidly secured to the stand 10 projects horizontally therefrom and has bolted thereto a pair of spaced upright journal members 31. An arm 32 is slidably carried upon the eX- tension 29 by means of a. rod 33 which is rigidly secured at its ends to the respective journal members 31 and traverses an apertured boss 34 disposed centrally of the arm 32. A pinl 315n extending at right angles from the arm 32 serves rotatably to support a reel 36 of resistance Wire 37, and af'cotter pin 38 traversingthe pin 35 prevents accidental displacement of the reel 36.

Theend ofthe arm 32 remote from the pin 35 is formed with an apertured boss 3.9 upon which asleeve 41 is` rotatably mounted and maintained in position, by means of'a nut 42 threaded on the boss. The Wire 37 in its passa e from the reel 36 to the circumference o "the tire carcass 18 is Wrapped a vplurality of'timesabout the sleeve 41 andlies in grooves 43 provi'dedfor. this purpose on the sleeve 41. shaft 4 4 is rotatably mounted in suitable bearings 45 provided` in the respective journal members'l31-` and traverses the bosses 39 ofthe arm A chain 46 trained about sprocket Wheels 47 and 48 which are keyed tothe shafts12 andr44, respectively, serves to rotate the shaftV 44k when the shaft 12v, and consequently the tire carcass 18 carried thereby, is rotated.

' A pivot pin 49 extending from the exterior to theA interior of the boss 39'has ypivotally connected toy its inner end a follower 51 which` isY disposed in a double thread 5.2 formedlupon the centralportion of the shaft Rbtationl of the shaft 44 causes movement ofk the-^ arm 32 longitudinally of the shaft 44 by reason of the arrangement of the follower 51 withinthe threads 52.

TheA provisiony of al double thread.y causes thearm` toreverse its direction o f movement antomatically when the. follower reaches either end of the double thread 52.,v The S IGketS 47 3.116148, as shown, arey of such size that the carcass 18 is rotated through approXimately 2.0 complete revolutions while thefarm travels from' oneend of the double thread to the other. It will be observedvthat provision of this particularfeed for the wire supplying mechanism obviatesthe necessity '0 resettlng the mechanism Vfor, operation Upon. eachV tire carcass. Then the wire. has

vbeenap ledtoonevcarcass and the latter is 'remove' f frbm thahaCl-i 135th@ Wife-,Supplying' mechanism is in proper position foi1 rapplying the wire to a second carcass, that is, the arm 32 moves in one direction for the winding of Wire upon one tire and in the opposite direction for the succeeding tire.

In practicing the invention the tire carcass4 18, having an airbag 19: disposed therein, isl mounted upon the pair of rings 21 which are secured together in the usual manner by the. bolts 2 2. This assembly is. then operatively positioned upon the chuck 13 by manipulation of the hand wheels 28. Although the, tire carcass, being composed of frictioned fabric elements, is capable of receiving and holding the resistance wire as it is wound thereon from the reel 36, it is preferablelirst to apply a gum strip 53 to the-portion ofthecarcass 18 which iste contactwi'th the tread 54.

A portion ofthe wire 37 spaced from the end thereof'is embedded adjacent one edge of the strip 53 and the motor 14 is energized to cause rotation of the carcass 18, together with movementl of the arm 32 axially of, and in synchronism with, the rotation of the carcass.

After the tread has been appliedtothe gum strip 537 which has the resistance wire 37 embedded therein, the carcass 18, the tread 54, the airbag 19 and the rings'21 are removed in assembledn relation from` the chuck' and a binder 55 is wrapped thereabout to retain the tread and carcass in proper assembled relation.

The ends 56 of the heating wire 37 are then connected to a source 57 of electrical current which results'in suiiicient heating of the spaced convolutions to insure proper vulcanization ofthe tread to the carcass. It is preferable to increase the inflation ,in the airbag slightl'yduring this operation in order to insure the'proper degree of pressure for. the vulcanizing'operation'. Y

From thevforegoing description it is apparent that a novel method of applying a tread toa tire carcass has been provided which is'r veryy simple, inexpensive and etlicient. The invention also provides a novel mechanism whereby an electrical heating element may be quickly applied to a rotating tire carcass in a novel manner.

Although I have illustrated only one form which may be employed in the practice of my invention, it will -be apparent to those skilled in the art that. the invention is not so limited, that the embodiment shown nis capable of various minor modifications, and that other embodiments may be employed Without departing from the spirit ofthe invention or from the scope of the appended claims.

TWhat I claim is:

l.. The methcdof Vslamming atreacl to a tire carcass which includes applying'an electrical conductor in spaced convolutions circumferentially of a` tire carcass, app-lying tread to the carcass, and passing an electric current through the conductor to vulcanize the tread to the carcass. y

2. The method of securing a tread toa tire carcass which includes mounting a tire carcass for rotation, attaching a portion of an electrical conductor to the carcass, rotating the carcass to draw thek conductor from a.

source of supply and moving the source of supply axially of the carcass as the latter is rotated, applying a tread to the carcass, coniining the tread and carcass, and passing an electric current through the conductor.

3. The method of securing a tread to a tire carcass which includes mounting a tire carcass or rotation, applying agum strip to the carcass, embedding a portion oi an'electrica-l conductor in the gum strip, rotating the carcass to draw the conductor from a source of Supply, ly of the carcass as the latter 1s rotated, applying a tread to the carcass, confining the tread and carcass, and passing an electric current through the conductor to vulcanize the tread to the carcass. A

4. The method of securing a tread to a tire carcass Which includes mounting a tire carcass for rotation, applying a gum strip to the carcass, embedding a portion of an electrical conductor in the gum `strip adjacent an edge thereof, rotating the carcass to draw the conductor from a source of supply, movd ing the source of supply axially of the carcass as the latter is rotated to cause erentially upon the carcass, applying a tread to the carcass, and passing an electric current through the conductor to vulcanize the tread to the carcass.k l

5. The method of securing a tread to a tire carcass which includes mounting a tire carcass or rotation, applying a gum strip to the carcass, embedding a portion of an electrical conductor in the gum strip adjacent an edge thereof rotating the carcass to draw the f the Winding of spaced convolutions of the conductor circumelectrical resistance unit upon the carcass of the tire, applying a semi-vulcanized tread unit to the carcass, and then raising the temperature of the carcass to the vulcanization point bypassing electrical current through Vthe resistance element.

In Witness whereof, Iy have hereunto signed my name. Y

Signed at Akron, in the county of Summit and State of Ohio, U. S. A., this 6th day of September, 1928.

WILL C. STATE.

moving the source of supply axial'- n i llo' vehicle tires which comprises Winding a plurality of spaced peripherally extending con-V volutions of an electrical resistance element upon the carcass of the tire, subsequently applying the tread element to the carcass and them raising the temperature of the tire to.

the vulcanization point by passing electrical current through the resistance element.

7 A method of manufacturing pneumatic vehicle tires which comprises disposing an 

